Water supply control systems have been developed to restrict the quantity of water delivered from a faucet or tap (generally referred to herein as a “tap”) in a single usage event. Such water supply control systems have also been used to prevent or restrict unattended outflow of water from taps. However, such water supply control systems tend to be complex and expensive to install and use. For example, in U.S. Pat. No. 6,003,170 a water supply control system is described comprising a mixer tap in the form of a single lever in combination with two separate electrically powered sensors and a controller. One of the sensors is mounted in the cap of the lever tap to detect mechanical movement of the lever and a second sensor is mounted on the underside of the tap to remotely detect physical presence of a user and electrical connections extend between each of the sensors and the controller. In addition, the hot and cold water supplies are fed to a mechanical mixer valve in the cap of the tap. The outlet of the mechanical mixer valve feeds a separate solenoid valve, mounted some distance away from the mechanical valve below the tap, and from the solenoid valve back up into the tap to the tap outlet.
A further problem with conventional water supply control systems arises from the fact that people who suffer from dementia or other forms of impairment of their mental processes can find it difficult to operate the tap or taps. Proper operation of remote sensors, in particular, can be difficult to comprehend for those suffering from impaired mental processes and so they can become confused when water does not start to flow out from a tap that they think they have turned on. As a result the adoption of water supply control systems in the care home environment and in facilities used by those suffering impairment of their mental processes can have the unfortunate effect of making residents/patients reliant upon staff for assistance.